Double lock connector

Abstract: A double lock device (1) having latching arms (2) and through holes (12) located in the vicinity of the ends of the latching arms (2) is placed in a connector housing (50). In a normal state, the lugs (10) of the latching arms (2) are locked in depressions (58) of the housing (50). In order to release this locking, the latching arms (2) are bent by a tool (80) whose tip (82) becomes engaged with the through hole (12). The double lock device (1) is extracted by moving the tool (80) in the direction shown by arrow B.

Description: This invention relates to double-lock connectors, especially to double-lock connectors having a double-lock device with a latching arm. Contacts arrayed inside connectors are usually placed into the contact cavity by means of a housing lance or some other device. Double lock devices are generally used in order to increase the retaining force holding these contacts inside the housing. A number of methods for latching in double lock devices has been offered ranging from a simple fitting of a protrusion in a notch to devices incorporating springy elements, such as, described in the Japanese Utility Model Publication No. 1992-23440. For example, Fig. 5 of the accompanying drawings represents a cross section of a conventional connector in which a double lock device with a latching arm is used. This connector 100 consists of a housing 102, a double lock 130 and a cover 120. Contacts and the cavity in which the contacts are retained are not shown in the drawing. The double lock device 130 is of approximately rectangular shape and, in the drawing, it is shown in the state when it is completely locked in the housing 102. At approximately midpoint of the double lock device 130, there are two latching arms 132 and 142 extending in opposite directions. In the vicinity of the free ends of the latching arms 132 and 142, lugs 134 and 144 respectively are provided. The double lock device 130 is inserted in the cavity 106 of the housing 102 from the side surface 104 of the housing 102. First, the lug 144 becomes engaged with a lug 108 of the housing 102, thus providing a state of temporary latching of the double lock device 130. Next, when the double lock device 130 is inserted even farther in, the lug 134 of the latching arm 132 becomes engaged with a lug 110 of the housing 102, thus completing the latching. Due to this complete latching, the contacts are prevented from being pulled out in the direction of their axes. Rarely, but in some cases, because of a damaged contact or improper wiring, it is necessary to remove the double lock device after it has been inserted. In such cases, the latching between lugs 124 and 110 is released by bending the latching arm 132 in the direction shown by the arrow A by pushing its end by a tip of a screw driver or some other tool. However, this design has the disadvantage that the latching condition between the latching arm 132 and the lug 110 can easily resume, thus making the task of removal of the double lock device 130 rather difficult. The aim of the present invention is to provide a double-lock connector which alleviates the above mentioned disadvantage. To this end, the invention consists in a double lock connector having a housing with a cavity for receiving a double lock device which serves to lock electrical contacts of the connector in passageways in the housing and which has latching arms for retaining the device in the cavity, characterized in that the double lock device has a tool receiving area proximate the latching arm such that the latching arms can be unlatched from the housing using a tool, whereupon the double lock device is removable from the cavity using the tool in cooperation with said tool receiving area and while the latching arms are held in the unlatched position by the tool. Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a front view of a double lock device for use with a double-lock connector according to this invention. Figure 2 is a cross section along the line II-II of Figure 1. Figure 3 is a cross section of the double lock device in a state when it is inserted in the housing. Figure 4 A is a cross section of the double lock device in a state preparating to being extracted with the help of a tool. Figure 4 B is a cross section of another embodiment of double lock device in a state preparating to being extracted with the help of a tool. Figure 5 is a cross section of a conventional double-lock connector. Fig. 1 is the front view of a double lock device 1 used in the double-lock connector according to this invention. The double lock device 1 is of approximately rectangular shape and it has at both ends cantilevered latching arms 2. The latching arms 2 can move in the direction perpendicular to the plane of the drawing. Rectangular openings 4 are openings for the insertion of contacts, not shown in the drawing. Items 6 and 8 are openings made in the double lock device 1. The latching arms 2 have lugs 10. Through holes 12 are made in the double lock device behind the latching arms 2. The design of these through holes can be clearly seen in the Fig. 2. Fig. 2 is a cross section of the double lock device 1 shown in the Fig. 1 along the line II-II. The latching arms 2 extend from approximately the middle point of the double lock device 1 along its side surface 14. An empty space 18 formed behind the latching arm 2 is provided to make room for the bending of the latching arm 2. The through hole 12 is made in the body of the double lock device 1 behind the free end of the latching arm 2. Along the side surface 16, a latching arm 20 having a lug 22 is made extending in the direction opposite to that of the latching arm 2. The lug 22 forms a temporary locking of the double lock device 1 when it is inserted in the housing 50 by interfering with the housing. Fig. 3 is a schematic longitudinal cross section of the above mentioned double lock device 1 in the state when it is inserted in the connector housing 50. In this drawing, for simplicity, the latching arm 20 for temporary locking is not shown. When the double lock device 1 is inserted in the cavity 56 of the housing 50, the lug 10 of the latching arm 2 is deflected by protrusion 54 of the housing 50 in the direction of the empty space 18. After it passes the protrusion 54, the latching arm 2, due to the spring action, returns to its original position, and the lug 10 locks in the depression 58 of the housing 50. This locked state is shown in the Fig. 3. Fig. 4 A is a longitudinal cross section of the double lock device 1 shown in the Fig. 3 in a state when it is removable from the housing 50. In this state, the free end 24 of the latching arm 2 is bent out in the direction of the empty space 18 by pushing it with the tip 82 of a screw driver or some other tool 80. Due to this action, the lug 10 of the latching arm 2 is released from the depression 54 of the housing 50, and the tip 82 of the tool 80 penetrates the through hole 12. After that, the tool 80 is moved in the direction indicated by the arrow B, thus removing the double lock device 1 from the cavity 56 of the housing 50. A modification of this embodiment providing for a better engagement of the tool 80 with the upper wall 13 of this through hole 12, is explained next with reference to Fig. 4 B. Fig. 4 B represents another embodiment of the double lock device 1' having a different configuration of the through hole 12'. This through hole 12' has a larger opening so that its bottom wall 14' comes to approximately middle point of the latching arm 2'. Because of this, the free end 24' of the latching arm 2' can be easily bent inside the through hole 12', and the tip 84 of the tool 80 can be easily engaged with the upper wall 13' of the through hole 12', thus making removal of the double lock device 1' in the direction of the arrow B more reliable. Preferred embodiments of this invention are described above. However it is to be understood that the invention also includes various modifications. For example, the space in which the tool tip is inserted may be a cavity, rather than a through hole of the housing. It also may be made in the form of protrusions extending from the housing. The double-lock connector according to this invention having a double lock device with a latching arm which can be bent by a tool has the following effect due to the fact that a means is provided in this double lock device for engagement of the tool tip with the double lock device. The double lock device can be easily extracted by the process of a simple operation. There is no danger of damaging the latching part during removal. Therefore, the reliability of the locking mechanism does not decline with use.

Claims: A double lock connector having a housing (50) with a cavity (56) for receiving a double lock device (1) which serves to lock electrical contacts of the connector in passageways in the housing and which has latching arms (2,2') for retaining the device (1) in the cavity (56), characterized in that the double lock device (1) has a tool receiving area (12,12') proximate the latching arm (2,2') such that the latching arms (2,2') can be unlatched from the housing (50) using a tool (80), whereupon the double lock device (1) is removable from the cavity (56) using the tool (80) in cooperation with said tool receiving area (12,12') and while the latching arms (2,2') are held in the unlatched position by the tool (80). The connector of claim 1, wherein the double lock device (1) has openings (4) to allow for insertion of the electrical contacts. The connector of claim 1 or 2, wherein the latching arms (2,2') have lugs (10). The connector of claim 1, 2 or 3, wherein the tool receiving area (12,12') is a through hole. The connector of claim 4, wherein the through hole (12,12') has a bottom wall (14') which is approximately at a middle point of the latching arm (2,2'). The connector of claim 5, wherein the latching arm (2,2') can be bent inside the through hole (12') and said tool (80) is engageable with an upper wall (13') of the through hole (12').

Inventors: TSUKAKOSHI MASAO, TSUKAKOSHI, MASAO
Applicants: WHITAKER CORP, THE WHITAKER CORPORATION
Application year: 1994
Main classification: H01R13
IPC codes: H01R13, H01R43